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Hongan Long
Postdoctoral Researcher

Ph.D., 2012, Biology, University of Houston

M.S., 2007, Marine Biology, Ocean University of China

B.S., 2004, Bioscience, Ocean University of China

I was a ciliate-centered researcher before joining the Lynch lab. After working on marine ciliates' morphology and taxonomy as an undergraduate researcher and M.S. student, I moved on to more conceptually grounded topics on mutation accumulation using the model ciliate Tetrahymena thermophila in Becky Zufall's lab at University of Houston. T. thermophila provides a wonderful playground for mutations to accumulate in its germline genome and hide from selection. It also turns out this system could be used to estimate other important population genetic parameters, besides the total deleterious mutation rate and fitness effects, lethal mutation rate and dominance coefficients. The estimates fell into the range of studied eukaryotic organisms.

My starting post-doc project is involved in exploring the impact of the DNA mismatch repair (MMR) system on mutation accumulation patterns. The study system uses Deinococcus radiodurans, the known organisms with the strongest resistance to radiation on the earth. Other projects focus on the broader mutation spectrum of microbial eukaryotes, which currently include: the red yeast Rhodosporidium toruloides, the mesometazoan Sphaeroforma arctica, as well as ciliates species like Paramecium biaurelia, Paramecium sexaurelia.

Selected Publications

Long, H., Paixao, T., Azevedo, RBR, Zufall, RA. 2013. Accumulation of spontaneous mutations in the ciliate Tetrahymena thermophila. Genetics 195: 527-540

Long, H., Zufall, RA. 2010. Diverse modes of reproduction in the marine free-living ciliate Glauconema trihymene. BMC Microbiology. 10: 108. 

Long, H., Song, W., Al-Rasheid, K., Gong, J. 2009. Three marine haptorid ciliates from northern China: Paraspathidium apofuscum n. sp., Trachelotractus entzi (Kahl, 1927) Foissner, 1997 and Apotrachelotractus variabialis Long, Song & Warren, 2009. Journal of Natural History. 43: 1749-1761;

Long, H., Liu, H., Liu, W., et al. 2008. Two new ciliates from Hong Kong coastal water: Orthodonella sinica n. sp. and Apokeronopsis wrighti n. sp. (Protozoa: Ciliophora). Journal of Eukaryotic Microbiology. 55: 321-330;

Long, H., Song, W., Wang, Y. and Li, J. 2007. Morphological redescription of two endocommensal ciliates, Entorhipidium fukuii Uyemura, 1934 and Madsenia indomita (Madsen, 1931) Kahl, 1934 from digestive tracts of sea urchins of the Yellow Sea, China (Ciliophora; Scuticociliatida). European Journal of Protistology. 43: 101-114;

Long, H., Song, W., Warren, A., et al. 2007. Notes on two new marine ciliates from the north China seas, Schizocalyptra aeschtae nov. spec. and Sathrophilus holtae nov. spec., with new definition of the poorly-outlined genus Sathrophilus (Ciliophora, Oligohymenophora). Acta Protozoologica. 46: 229-245;

Long, H., Song, W., Chen, J., et al. 2006. Studies on an endoparasitic ciliate Boveria labialis (Protozoa: Ciliophora) from the sea cucumber, Apostichopus japonicus. Journal of Marine Biological Association, U. K. 86: 823-828.

Long, H., Song, W., Gong, J., et al. 2005. Frontonia lynni n. sp., a new marine ciliate (Protozoa, Ciliophora, Hymenostomatida) from Qingdao, China. Zootaxa1003: 57-64.

Long, H. 2000. A useful solid geometry function. Mathematics and Physics World (High School Edition, in Chinese). 71: 42.